Garmin .gdb MapSource files, are files designed to be used with Garmin GPS
units to transfer routes, maps and information.

.gpx eXchange is a light-weight XML data format for the interchange of GPS data (waypoints, routes, and tracks) between applications and Web services on the Internet. Most GPS software will be able to open these files.

As trails change
blaze colors and can be rerouted having a GPS unit is a great
way to see exactly where you are along your hike.

Whichever Garmin unit you have you will need the TOPO three CD set
that will allow you to select maps and create routes and way
points. Nearly all of the Garmin GPS units will transfer the
route portion of the file and graphical
Garmin GPS units will also transfer selected map(s).

All hikes on this site contain a link to a Garmin MapSource
file, and are being updated to include the universal .gpx eXchange files as well.Note: You need
to have the TOPO CD's installed on your system to transfer the
maps with the .gdb files.